To comprehend speech is to obtain meaning from spoken words. Intelligibility is a quality which enables spoken words to be understood. In a typical language, any given word will have a number of “sound-alike” words. The existence of these sound-alike words can make it difficult for the listener to identify words easily, quickly, and accurately from natural or synthesized speech. A word with low intelligibility can make identification even more difficult.
Many factors can influence intelligibility, such as the abilities or qualities of the human speaker or artificial speech synthesizer, the abilities or qualities of the human listener or electronic speech recognition device, and the presence of background noise. When the speech is electronically transmitted to a listener, even more factors can influence intelligibility, such as the quality of the transmission equipment, receiving equipment, and playback equipment.